The purification of small amounts of non-potable water for individuals or households has been accomplished through various methods. Some methods involve pumping water through a filter to remove harmful bacteria while still other methods use chemicals such as halogens including chlorine, bromine and iodine. Some methods, which use a source of silver ions as a disinfectant, require one to pretreat the water in order to use silver ions purify the water.
One of the difficulties in creating potable water in small amounts is the need to quickly generate potable water from non-potable water. U.S. Pat. No. 6,010,626 shows a pump that quickly generates potable water by forcing nonpotable water through a filter to remove bacteria and other debris. While such devices can work effectively for filtering out certain types of bacteria they usually require extensive hand pumping to generate a small amount of potable water since a large force is required to force the water through the small pores in the filter. A variety of different methods and apparatus are used to render non-potable water potable as evidenced by the following patents:
U.S. Pat. No. 4,894,154 shows an example of an individual portable water treatment device that uses a pleated membrane-filtering cartridge.
U.S. Pat. No. 7,390,343 shows a device for removing harmful organisms from non-potable water with nano alumina fibers having particles of metals such as silver, copper or zinc deposited on the nano alumina fibers.
U.S. Pat. No. 4,349,512 shows an improved bacteriostatic filter media for home use that uses a bacteriostatic filter media comprising silver treated cellulose and powdered carbon.
U.S. Pat. No. 4,267,455 shows another type of a water purification device that uses UV tubes that extend through a chamber in the vessel.
U.S. Pat. No. 7,441,665 discloses a water purification cartridge for use in a gravity feed filtration discloses the use of a water purification medium that may include a halogenated polystyrene hydantoin, a halogenated polymeric sulfonamide resins, a halogenated hydantoin siloxane and a halogenated polystyrene traiznedione.
U.S. Pat. No. 4,695,379 discloses a water treatment bottle that includes a cap that can be placed on a bottle with the cap including a tube that contains a water treatment material such as carbon, silver impregnated coral sand, ion exchange resins to remove contaminants normally present in tap water.
U.S. Pat. No. 4,198,296 shows pretreating the water to remove halide ions so that the silver ions from the silver activated charcoal media can disinfect the water.
Some of the difficulties with the aforedescribed devices and methods is that some types of filtration device require considerable work on part of the user to generate potable water thus discouraging their use. Still others require an extended length of time for the purification agent to render the water potable and still others require pretreatment of the water before the water can be disinfected.